Fabricated cylinder head-en-block



March 21, 1961 o. w. WILCOX FABRICATED CYLINDER HEAD-EN-BLOCK Filed July25, 1957 4 Sheets-Sheet 1 Fig.1

March 21, 1961 o. w; WlLCOX 2, 75,

FABRICATED CYLINDER HEADENBLOCK Filed July 25, 1957 '4 Sheets-Sheet 2 g2 INVENTOR March 21, 196] o. w; WlLCOX FABRICATED CYLINDER HEAD-EN-BLOCK4 Sheets-Sheet 4 Filed July 25, 1957 INVENTOR W [0. 404

FABRlCATED CYLINDER HEAD-EN-BLOCK Orland W. Wilcox, Pasadena, Calif.(3080 N. Fair Oaks Ave., Altadena, Calif.)

Filed July 25, 1957, Ser. No. 674,090

4 Claims. (Cl. 123-195) This invention relates to internal combustionengines and more particularly to a cylinder head-en-block constructionand more especially to the design and method of fabricating the same.

The general purpose of the invention is the bringing together, in ahydrogen-atmosphere furnace, of sheet metal stampings and associatedsteel parts into a permanently unitary structure of cylinderhead-en-block configuration and a copper brazing or welding thereof by aheat fusionprocess. A cylinder head-en-block is a configurationembodying a plurality of cylinders, the head and ports associated witheach cylinder, and the water jacket surrounding cylinders, cylinderheads, and associated parts. 7 H

Several methods of heat treatment have been in use for some time andthese include electric welding, gas welding, induction welding andinduction brazing, and furnace brazing. Of these types furnace brazingappears to be the most satisfactory for cylinder head-enblockfabrication, provided, of course, a thorough analysis of the fabricationtechniques has been made.

Itis therefore the principal object of the invention to provide acylinder head-en-block which is made entirely of sheet metal and tubingand which is furnace welded into a unitary structure. a

Another object of the invention is to provide a light weight cylinderhead-en-block which is suitable for use where high performance is neededfor extendedperiods.

Another object of the inventionis to present an improved method offabricating a cylinder head-en-block so that warpage and leakage are notencountered.

7 Another object of the invention is to provide a cylinder head-en-blockwhich has greatly improved heat transfer 7 2,975,778 Patented Mar. 21,1961 ice Figure 5 is a partial view in section of one of the hold-downtube slip joints.

Figure 6 is another view of the same, showing the hold-down bolt tubeslip joint after subsequent welding and machining.

Figure 7 is a detail of a staked bushing which houses an O-ring (notshown).

Figure 8 is a perspective view of a cylinder having a modified head unitcomprising a stamping, each half stamping making up :a half of eachintake an exhaust port, and half of each passageway for the valve guidereceptacles, and one-half of the cylinder head.

Figure 9 is a View of a single stampingwhich makes up half of a modifiedcylinder unit which includes the cylinder, the head, and the intake andexhaust ports, and involved tubes.

Figure 10 is a perspective view of a cylinder head, associated ports,and valve guide receptacles of a nonsymmetrical stamping.

A cylinder head-en-block is a unitary structure comprising thecylinders, the cylinder heads, the communicating ports, or conduits,leading to and from the intake and exhaust manifolds, the valve guidereceptacle pas sageways, and the water jacket which surrounds theseparts.

The preferred embodiment of this invention, shown in Figure 1, is afour-cylinder, in-line engine. A cast camshaft housing is mounted on topof this cylinder head-en-block, and a cast crankcase is securedunderneath it. The camshaft housing, cylinder head-en-block, andya castcrankcase are bolted together with ten, long, through bolts which passthrough the cylinder head-enblock at positions where the hold-down bolttubes washers 14 are shown in Figure 1. I l

The water jacket comprises a single sheet 11, folde into seven surfacesresembling an inverted U, a pair of ends 12, and a bottom plate 26. ThisWater jacket sheet 11 is preferably made from a relatively thin gaugesheet steel. Various steels are suitable for this purpose; however, ithas been found that a high strength, highly corrosion-resistant steel,sold under the United States Steel Corporation trademark of Cor-ten, issatisfactory for this water jacket.

characteristics when compared with the conventionalcast head-en-block. 1

Another important object of the invention is to provide unique methodsand designs for fabricating a cylinder head-en-block with highturbulence, hemispherical;

or squish type combustion chambers.

A further object of the invention is to provide a cylinder head-en-blockconstruction of basic simplicity.

Other objects and advantages will appear and be brought out more fullyin the following specifications, reference being had to the accompanyingdrawings,

wherein: a

Figure 1 is a perspective view of a fabricated cylinder head-en-blockhaving four cylinders, the view being taken from the side which bestshows the intake and exhaust ports to the cylinders.

Figure 2 is an end view of the cylinder head-en-block with the waterjacket end plate removed and with appropriate break-out sections to showthe engine internal The water jacket has a top plate portion 13 and abottom plate 26 through which extend hold-down bolt tubes 31, washers14, a top portion 13., spacers'44, and a cylinder reinforcing ring 24,which rests on bottom plate 26. Valve guide receptacles 32 extend to thetop portion 13 of the water jacket and are secured by washers 15. Afterthe cylinder head-en-block has been welded into a unitary structure, thewashers 14 and 15 are machinedto form a flat surface illustrated inFigure 6.

Figures 1 and 2 show exhaust manifold mounting flanges 16 and intakemanifold mounting flanges 17 which are disposed on different surfaces ofthe aforementioned water jacket folded sheet 11. These flanges areprovided with the bolt receptacles 21 for securing the manifoldsthereto. I

The numerals 18 and 19 respectively refer to the exhaust and intakeelbows, or conduits, and may be referred to just as ports, and theseports, or conduits, extend through the water jacket and are welded intoa unitary structure.

A spark plug access tube 33 is provided for each cylinder and extendsthrough a surface of portion 20 of the water jacket which is inclined asshown in Figure 2.

The manifold bolt receptacles 21 have a two-fold pur- A pose, which istohold the manifold mounting flanges 16 and 17 and the Water intakemounting flanges 38 rigidly to the water jacket, and also to provide athreaded receptacle for the bolts which will be used to hold the intakeand exhaust manifolds (not shown) and the'water-hose flange (not shown)to their respective flanges.

Cylinders which are indicated 22 extend through and are secured rigidlyto the water jacket bottom plate 26, there being cylinder reinforcingrings 24, and cylinder staking rings 25, which aid strengthening thewater jacket where the cylinder goes through the bottom plate 26. Thecylinder bottom lip is rolled or staked to the cylinder staking ring 25.

After the cylinder head-en-block is'filrnace-brazed, this jointefiectively becomes a unitary structure. The upper end of the cylinder22 fits into a cylinder head 23, as is clearly shown in Figures 2 and 3.A slip joint 30 being provided between each cylinder audits head, mustbe held to a minimum clearance of substantially 0.0005 inch.

The Water jacket bottom plate 26 is secured to the water jacket 11' withthe use of bottom plate holding strips 28 which strips are spot weldedto the jacket 11 Similar strips (not shown) are spot weldedto the waterjacket end plates 12 to hold the ends of the water jacket bottom plate26. A copper wire 29 is positioned in these holding strips 28 to providean ample source of bonding copper at this joint. The joint between thebottom plate 26, water jacket 11, and holding strips 28, is intended tobe a slip joint similar to slip joint 30.

The cylinder head 23 as shown in Figures 2 and 3 is of a configurationto create high turbulence which is popularly known as squish typecylinder head. This head 23 is a sheet metal stamping. The intake port19 is made of two stampings, spot welded together for preliminaryassembly. Figure 3 shows one of the intake port stampings 39. Thisstamping includes passageways for the valve guide receptacles 32. Themating part to stamping 39 is a mirror image of stamping 39. The intakeport 19 is held rigidly to the cylinder head 23 with the threaded valveseat 40. The exhaust port 18 is made of two stampings spotwelded'together similar to that for the intake port 19, and the exhaustport 18 is rigidly held to the cylinder head 23 with a threaded valveseat 40 likewise.

A threaded coupling 35 holds each port, either intake 19 or exhaust 18,the associated manifold mounting flange 16 or 17, and the water jacket11 together rigidly. Each 'valve guide receptacle 32 is pressed intoposition, spot welded, and thereafter the top lip rolled onto the valveguide receptacle washer 15, as clearly seen in Figures 2 and 3. Therolled lip of the valve guide receptacle holds the port, the washer 15,and the water jacket'top surface 13 together rigidly.

The spark plug access tube 33 and the cylinder head 23 are held inproper alignment to each other with the spark plug threaded sleeve 34,as shown in Figure 2. The spark plug threaded sleeve 34 has both endsrolled over to hold the cylinder head 23 and the spark plug access tube33 rigidly together for preliminary assembly. Following the furnacebrazing cycle, this sub-assembly is a strong, water-tight, gas-tight,unitary joint, and the threaded sleeve 34 then serves as the receptaclefor the spark plug. The top end of the spark plug access tube 33 isrigidly held to the appropriate water jacket surface 20 by rolling thelip of the tube as shown in Figure 2.

The water distribution manifold 36 runs the length of the cylinderhead-en-block. It is spot welded to the inner side of the water jacket11 prior to brazing. A novel feature of this water distribution manifold36 exists in the nozzles 37 which are essentially punched orifices inthe manifold. The nozzles 37 are positioned to direct a stream of waterdirectly at the spark plug threaded sleeves 34. The water is thendiverted onto the valve ports 18 and 19 at approximately the threadedvalve seats 40. Thus the spark plugs and valve seats 40 which areparticularly subject to malfunction due to heat, are

given the advantage of maximum cooling since the lowest temperaturecooling water available impinges directly on them.

Figure 4 illustrates one of the hold-down bolt tubes 31 in its preferredform. It serves in three distinct capacities:

The initial purpose of each hold-down bolt tube 31 is to act as a long,hollow rivet. At the top end it shoulders against the reinforcing washer50, and when its upper lip is riveted over, the hold-down bolt tubewasher 14, the water jacket top surface 13, and the reinforcing washer50, are held together rigidly. At the lower end it shoulders against thehold-down bolt tube. reinforcing washer 45, and when its lower lip isstaked, or rolled, over, the hold-downbolt tube staking washer 43, thewater jacket bottom plate 26, the adjacent cylinder reinforcing rings24, the spacer 44, and the reinforcing washer 45, are held togetherrigidly. Each hold-down bolt tube 31, when staked over at both ends,acts as a spacer maintaining the distance between the. water jacket topsurface 13, and the water jacket bottom plate 26. It also acts as themeans for holding the entire assembly together prior to rolling the edgeof the water jacket 11 and the water jacket end plates 12, as shown bythe rolled edge 27. The rolled edge 27 locks the entire cylinder unitinto the confines of the water jacket proper. The rolled edge 27 alsostitfens the water jacket 11, and the water jacket end plates 12 at thislower joint.

The second major purpose for the hold-down bolt tubes 31 is to act as acompression member when the camshaft housing (not shown), the cylinderhead-en-block, and the crankcase (not shown) are bolted. together. Thehold-down bolts are torqued up to provide greater bolt tension thanwould be experienced in the bolts during operation of the engine. Thisis done so that the cylinder head-cn-block will not lift off of thecrankcase. For high performance operation at high compression ratios andhigh revolutions per minute the hold-down bolt tension necessary forsuccessful operation would distort the water jacket if the hold-downbolt tubes 31 were not provided. The camshaft housing (not shown) isdesigned to act as a strong back for the fabricated cylinderheaden-block.

The final and obvious reason for the hold-down bolt tubes 31 is toprovide a water-tight passage for the holddown bolts.

A step-by-step description of the forces involved during the heatinghalf of the brazing cycle will show how this simple, clean designaccommodates the distorting forces which could be caused by severetemperature differentials within the cylinder head-en-block. When themechanically assembled cylinder head-en-block is transported into thefurnace, which is maintained at 2100 F., the Water jacket heats veryrapidly. Assuming that the water jacket at one given instant is 1000 F.hotter than any of the internal parts, it can be understood whyprovisions for this temperature differential must not be ignored. Twopieces of steel 12 inches long, at ambient temperature, would measure ofan inch difference in length, should one piece be heated to 1000 F.hotter than the other. The stress necessary to restrain the heatedpiece, or to elongate the cooler piece of steel would be approximately120,000 p.s.i. The yield strength of suitable stamping sheet steelranges from 20,000 p.s.i. to 80,000 p.s.i. Thus it is explained whypermanent distortion may beexperienced during the brazing cycle.

The cylinder units are independent of one another (they are notinternally connected to one another in any manner) and are essentiallyfloating in the water jacket as the water jacket expands lengthwise. Thewater jacket also expands heightwise very rapidly. This heightwiseexpansion is taken up two ways: The hold-down bolt tubes31 expand slowerthan the water jacket 11; consequently the bolt tubes 31 force the waterjacket bottom plate lip 26 to enter deeper into the slip joint at theholding strip 28. The hold-down tubes 31 heat up faster than thecylinders 22, because the cylinders are of heavier material. Assumingthat all parts reach furnace temperature before the cylinders 22, wefind that slip joint 30 has allowedthe cylinder 22 to pull out of thecylinder head 23 a short way. When the cylinder 22 reaches furnacetemperature also, it slips all the way back into the cylinder head 23. 7Thus the slip joint 30 relieves anticipated stresses. 7 g i Thecooling-01f half of the brazing cycle is relatively simple. Thecylinder-head-en-block cools evenly and slowly as it drops intemperature 300 F. The slow, even cooling gives the copper a chance tosolidify and to bond all the parts together into a unitary structure.The brazed joints are stronger than the parent metal by the time thestructure has cooled to 1550 F.; so it is then safe rapidly toair-quench the structure in order to refine the grain size ofchrome-molybdenum steel cylinders. One design precaution must beobserved before attempting the air quench from a high temperature of1550 F. This precaution is that the cylinder uni as a unitary structuremust be stronger in column loading than the water jacket surrounding it.

Figure 5 shows the hold-down bolt tube 31 held in a slip joint formed bya slide bushing 41. The slide bushing 41 is staked over the hold-downbolt tube washer 14. This design would allow the water jacket to be madein some configuration wherein the bottom plate 26 would not be able tomove. Figure 6, as previously explained, is primarily to show a rolled(or staked) joint after it has been machined to provide an accuratesurface.

Figure 7 is a detail of a staked bushing 42, which houses an O- ring(not shown). The application of'this type of bushing would be where ahold-down bolt tube 31 was not needed. The staked bushing 42 would allowa hold-down bolt (not shown) to pass through the water,

jacket 13 and the O ring would effect a Water seal be-' tween the boltand the bushing .42.

cylinder head stamping 46,- shown as the mating stamping 46a, also. Thecombination symmetrical cylinder head stamping 46 makes up half of eachport (intake and exhaust), half of each passageway for the valve guidereceptacles, and half of the cylinder head. Two

of these stampings are spot welded together and accomplish the samepurpose as the five individual stampings in Figure 2. The symmetricalfeature of this stamping 46 makes it unnecessary to have more than oneset of stamping 'dies.

Figure 9 shows a single stamping 47 which is intended to serve as halfof ,the cylinder as well as half of all the other functions whichstamping 46 accomplishes. The half cylinder unit stamping 47 can be madeof chrome-molybdenum steel sheet stock, or it can be cast or forged fromsome of the other appropriate steels. Made of the proper steel, thevalve seats can be ground out of the parent stamping 47. Two stampings,such as 47, may be welded together by higher temperature means thancopper brazing and maybe done prior to brazing thus simplifying thewater jacket brazing process.

The cylinderhead. depicted in Figure 10 shows the use of twonon-symmetrical combination cylinder head stampings 48} and 49. Eachstamping makes up half of each port (intake and exhaust), half of eachpassageway for the valve guide receptacles, and half of the cylinderhead. The design features of Figure 10 include maximum and unrestrictedinduction porting, and the possibility of using different size intakeand exhaust valves.

Figures 8, 9, and 10 show a bridging strip 51 between the intake andexhaust ports." This bridging strip 51 adds considerably to the domestrength of a hemispherie cal combustion chamber.. Thebridging strip,and the ports form a triangle which stifiens the dome, reducing I r .35The hemispherical combustion chamber is very often conduits, and a webextending between the inlet and exhaust conduits.

References Cited'in the file of this patent UNITED STATES PATENTS1,113,124." Jacobs Oct. 6, 1914 1,133,531 Breath "Mar. 30, 19151,270,044 Murray June 18, 1918 1,402,695 Wall Jan. 3, 1922 1,621,521Cappa Mar. 22, 1927 2,011,642 Loefiler Aug. 20, 1935 2,199,423 TaylorMay 7, 1940 2,275,478 Taylor Mar. 10, 1942 2,337,577 Taylor Dec. 28,1943 2,341,488 Taylor Feb. 8, 1944 1 2,444,963 Taylor July 13, 19482,578,079 Meinertz Dec. 11, 1951 the flexing caused by the' compressionstroke and the I. 1

power stroke of the gas charge in the cylinder.

Having described my invention what I claim is:

adaptation to an internal combustion engine consisting of a plurality ofcylinder units, each cylinder unit comprising as components a tubularcylinder, a head, inlet, exhaust, valve guide, and spark plug conduitscommunicating with said head, and 'a sheet metal water jacket throughwhich all of said'components exclusive'of said head, extend, all of saidcomponents and said Water jacket being secured together by a heat fusionprocess, each said head comprising a sheet metal stamping having aperipheral portion transverse to the cylinder axis adjacent the top ofthe cylinder so formed as to provide high turbulence of a fuel charge insaid cylinder.

2. A fabricated cylinder head-en-block structure for adaptation to aninternal combustion engine consisting of a plurality of cylinder units,each cylinder unit comprising as components a tubular cylinder, a head,inlet, exhaust, valve guide, and spark plug conduits communicating withsaid head, and a sheet metal water jacket through which all of saidcomponents exclusive of said head, extend, all of said components andsaid water jacket being secured together by a heat fusion process, saidwater jacket including top and bottom plates for mounting respectively acam shaft housing and crank case, and

a plurality of bolt hold-down tubes extending through and secured tosaid top and bottom plates.

3. A fabricated cylinder head-en-block structure for adaptation to aninternal combustion engine consisting of a plurality of cylinder units,each cylinder unit com prising as components a tubular cylinder, a head,inlet,

exhaust, valve guide, and spark plug conduits communicating with saidhead, and a sheet metal water jacket through which all of saidcomponents, exclusive of said head. extend, all of said components andsaid water jacket being secured together by a heat fusion process, eachsaid cylinder head comprising a pair of half stampings, jointly formingsaid conduits, eachcylinder unit including a pair of mirror imagestampings, each of said stampings forming one-half respectively of ahead, inlet, ex-

haust, and valve guide conduits, and a web extending between the inletand exhaust conduits.

4. A fabricated cylinder head-en-block structure for adaptation to aninternal combustion engine consisting of aplurality of cylinder units,each cylinder unit comprising as components a tubular cylinder, a head,inlet,

exhaust, valve guide, and spark plug conduits communi- 2,817,327Brenneke Dec. 24, 1957

